Shoe press pad



Jinan May 15, 1956 Filed Aug. 19, 1953 M. C- SUERKEN SHOBPRESS PAD 2Sheets-Sheet l INVENTOR.

MVMCM y 15, 1956 c. SUERKEN 2,745,123

SHOE PRESS PAD Filed ug. 9. 1953 2 Sheets-Sheet 2 QQODOOOGOOO 52 FIG. 7

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United States Patent SHOE PRESS PAD Maxwell C. Suerken, Erie, Pa.,assignor to Lamac Process Company, Erie, Pa., a corporation of DelawareApplication August 19, 1953, Serial No. 375,087

Claims. (Cl. 12-38) In shoe sole cementing machines, it may be desirablethat the unit pressure be higher at the shank than at the heel and toeso that the force dissipated in conforming the shank of the sole willnot result in inadequate cementing pressure. This invention is intendedvto achieve this result in machines using inflatable pressure pads. Useis made of an auxiliary'pad resting on the casing of the inflatable padunder the shank of the sole and having substantially greater area thanthe shank. Lateral stiffening rods embedded in the auxiliary pad permitflexing in a longitudinal direction or lengthwise of the shank, but makethe pad essentially rigid in a direction crosswise of the shank. Thisresults in a total force on the shank of the sole proportional to thearea of the auxiliary pad rather than to the area of the shank andaccordingly increases the unit pressure at the shank so that thepressure is adequate both to conform the shank of the sole and toprovide the desired cementing pressure.

In the accompanying drawings, Fig. 1 is a side elevation partly insection of a shoe cementing press in the closed position; Fig. 2 is atop plan View of the shoe press pad; Fig. 3 is a section on line '3-3 ofFig. 1 with the shoe shown in dotted lines; Fig. 4 is a section on line44 of Fig. l with the shoe shown in dotted lines; Fig. 5 is a section online 5-5 of Fig. 4 with the shoe .shown in dotted lines; Fig. 6 is a topplan view of the auxiliary pad underlying the shank portion" of thesole; Fig. 7 is anend view of the auxiliary pad; and Fig. 8 is a diagramof the unit pressure exerted on the heel, shank, and toe sections of thesole being cemented.

The invention is shown applied to a press of the construction disclosedin Patent 2,654,104, granted October 6, 1953. As there disclosed ingreater detail, the press unit is mounted on a frame 1 and comprises alower frame 2 having its base 3 suitably fixed to the top 4 of the frame1 and a pressure arm 5 pivoted at 6 on the lower frame 2. The pressurearm 5 is biased to the raised position by a tension spring 6:: attachedto a bell crank lever 7 pivoted at 8 on the lower frame 2. The bellcrank lever has an arm 9 pivoted to a link 10 carried by a depending arm11 on the pressure arm. The links 9 and 10 serve as a toggle lever formoving the pressure arrn between open and closed positions. In theclosed position, the arm 9 strikes an adjustable stop 12, which isadjusted so the common pivot 13 of the toggle lever is slightly abovethe center line of toggle linkage. When the press is open, as shown indotted lines, the pressure arm 5 is raised and heel and toe pressuremembers 14 and 15 are sufliciently above a pressure pad 16 to permitconvenient insertion and removal of a shoe 17 on a last 18 and having asole 19 which is to be cemented. This gives the operator space to loadand unload. Each of the heel and toe pressure members is carried at thelower end of an adjusting screw 20 adjustable both lengthwise and up anddown of the pressure arm 5.

The pressure pad 16 is carried in a box-shaped base 21 having side andend walls 22 and 23 surrounding the edges of the pad. Within the base isfixed a sole plate 24 2,745,123 Patented May 125,, 1956 "ice and apivoted heel and shank plate 25, which is adjustable by means of a screw26 to accommodate different types of shoes; The base 21 is suitablysecured to the base 3 of the frame 2.

As shown in greater detail in Figs. 3 and 4,. the pressure pad comprisesan envelope or casing 27 usually of leather with an inflatable bladder28.

The press is closed by a foot pedal 29 pivoted at 30 on the frame 1. Thecementing pressure is developed by air pressure supplied through lines48, 46 leading to valve stem 47 on the rubber bladder 28, the padpressure is released by venting the pressure through lines 45, 46 andthe press is opened by the spring 6a after the pad pressure is released.

As far as the present invention is concerned, other shoe cementingpresses may be used. The pressure exerted on the sole comes frominflating pressure in the bladder of the shoe press pad rather than fromthe construction of the press. I

When the bladder 28 is inflated, the air pressure exerts a uniformpressure over the entire inner surface of the bladder. Although thispressure is likewise transmitted essentially uniformly to the pad casing27, some of the force is dissipated in making the sole 19 conform to theshoe so that the effective cementing pressure actually transmitted isnot uniform throughout the area of the sole. It is accordingly desirablethat a higher unit pressure be exerted at the shank area 49 of the solethan at the heel 50 or toe 51. The shank 49 is the part of the solewhich undergoes the greatest deformation in conforming to the shoe,particularly in the type of shoe illustrated where the sole must, inaddition, conform to the breast 52 of the heel; higher pressures in theshank section of the sole were desirable in order to obtain the uniformcementing.

obtained by the auxiliary pad 53 shown in Figs. 6 and 7,

which is mounted on the shoe pad casing 27 under the shank 49 of thesole. The pad has a body of, a suitable elastomer such as naturalorsyntheti'c rubber or plastic having a wedge-shaped upper surface withan 'inclined section 54 under the shank of the shoe and an inclinedsection 55 under the breast of the heel. It is expected that the userwill buff the surfaces 54 and 55 so as to fit any particular style ofshoe. The pad 53 is essentially rectangular in shape and has a widthsubstantially greater than the width of the shank 49 of the sole. Aplurality of lateral stiffening rods 56 are embedded into the pad.Because these stiffening rods 56 extend crosswise of the pad, the pad isfree to flex lengthwise along the shank 49 of the sole, but isessentially rigid in a direction crosswise of the shank of the sole.From one aspect the surface of the pad underlying the shank of the solebehaves as though it were made of rigid strips or lamina extendingcrosswise of the pad and covered with elastic or flexible materialconforming to the shank. The operation would be the same if theauxiliary pad were built into and formed part of the pad casing or aflexible cover for the complete top surface of the pad casing. In fact,the auxiliary pad acts as though it were part of the top surface of thepad casing. Two of the rods 57 extend out each side of the auxiliary pad53 and are hooked into suitable eyelets 58 in a leather strap 59, whichunderlies the shoe press pad and has its free ends extending up alongthe side of the pad opposite the shank portion 49 of the sole. Theauxiliary pad 53 will work in the same manner, whether anchored in placeby the strap 59, or whether merely resting loosely on the upper surfaceof the pad casing 27. The strap 59 is merely a convenient way of holdingthe auxiliary pad in the proper location so that the operator will notbe disturbed by having to relocate the auxiliary pad in case itaccidentally becomes It has long been recognized that displaced from thecorrect position. By this construction, he total force transmitted tothe auxiliary pad 53 from the casing 27 of the inflated pad 16 issubstantially equal to the unit pressure exerted by the bladder 28 timesthe area of the auxiliary pad 53. Since the auxiliary pad 53 isessentially rigid in a crosswise direction, the force exerted on theshank 49 is directly transmitted to the shank 49 and as shown in Fig. 8,the unit pressure exerted on the shank 49 is substantially greater thanthe unit pressure exerted on the heel 50, or toe 51. This is preciselyWhat is required for adequate cementing.

If the stiffening rods 56 were omitted, the auxiliary pad 53 wouldmerely be buried deeper into the casing 27 and the unit pressure exertedon the shank would not be substantially increased. The stiffening rods56 are necessary in order that the pressure exerted on the shank may beproportional to the length of the rods rather than to the unit pressurewithin the bladder. With this construction, the unit pressure exerted onthe shank 49 of the sole is increased by a factor equal to the ratio ofthe length of the rods 56 to the Width of the shank portion of the soleunderlying the rods. While the shank 49 of the sole is flexedconsiderably in a direction lengthwise of the shoe, in a crosswisedirection the shank is essentially flat or possibly slightly curved. Thecurvature is slight enough so that the resilience of the elastomer,which comprises the body of the auxiliary pad 53, is sufficient toconform to the shank of the sole.

Cementing presses are used for forming or sole-laying, even though thesole is not cemented to the shoe and the higher unit pressure on theshank of the sole is advantageous in this use.

What is claimed as new is:

1. In a shoe press, a pad having an inflatable casing for pressing asole against a shoe, the casing having a surface underlying the sole andbeing substantially wider than the sole at the shank of the sole, anauxiliary pad substantially wider than the shank of the sole formingpart of said surface of the casing beneath the shank, said auxiliary padbeing flexible in a direction lengthwise of the shank and rigid in adirection crosswise of the shank whereby the unit pressure exerted onthe shank of the sole is higher than over the remainder of the sole.

2, In a shoe press, a pad having an inflatable casing for pressing asole against a shoe, the casing having a surface underlying the sole andbeing substantially wider than the sole at the shank of the sole, anauxiliary pad substantially wider than the shank of the sole formingpart of said surface of the casing beneath the shank, said auxiliary padhaving a body of flexible material with longitudinally spacedreinforcing rods therein extending crosswise of the shank.

3. In a shoe press, a pad having an inflatable casing for pressing asole against a shoe, the casing having a surface underlying the sole andbeing substantially wider than the sole at the shank of the sole, anauxiliary pad having a body of an elastomer substantially wider than theshank of the sole forming part of said surface of the casing beneath theshank, and means restraining flexing of the body in a directioncrosswise of the shank but not lengthwise of the shank whereby the unitpressure exerted on the shank of the sole is higher than over theremainder of the sole.

4. The construction of claim 3 in which the restraining means comprisesrods embedded in the body extending crosswise of the shank and spacedapart along the length of the shank.

5. In a shoe press, a pad having an inflatable casing for pressing asole against a shoe, the casing having a flexible top surface underlyingthe sole and being substantially wider than the sole at the shank of thesole, and the portion of the surface engaging the shank of the solecomprising elastic material overlying rigid lamina extending crosswiseof the shank and spaced apart lengthwise of the shank whereby theportion of the surface engaging the shank of the sole is flexible in adirection lengthwise of the shank and rigid in a direction crosswise ofthe shank whereby the unit pressure exerted on the shank of the sole ishigher than over the remainder of the sole.

References Cited in the fileof this patent UNITED STATES PATENTS 388,377Smith Aug. 21, 1888 1,160,983 Hemanover Nov. 16, 1915 1,910,858 Ruhr May23, 1933 1,953,224 Hazleton Apr. 3, 1934 2,187,828 Finn Jan. 23, 19402,255,155 Farnum Sept. 9, 1941 2,497,195 Woodman et a1. Feb. 14, 1950

